If you're creating your 1st baby steps within the world of cryptocurrency, you're probably searching for the cheapest way to buy bitcoin. As you already grasp there are multiple choices how you can purchase digital coins: exchanges (e.g. CEX.IO, Changeling, VirWox), brokers (e.g. Coinmama, xCoins, Coinbase) friends, peer-to-peer platforms (e.g. LocalBitcoins, Paxful) or even Bitcoin ATMs. you'll be able to also choose a way of payment that is convenient for you and available in your country: wire transfer, debit/credit card, cash, PayPal, Walmart card or even Amazon gift cards.
Steps to buy Bitcoin:
Have fiat money (USD, EUR) on your bank account (debit/credit card)
Select a Bitcoin wallet for your future investment and register there to get the wallet address (e.g. electrum Wallet).
Select the exchange, register there and link it to your bank account and Bitcoin wallet.
Buy the desired quantity of BTC.
Transfer your crypto to the wallet for safe storage.